Mathematical modeling of the heat transfer processes in the melting chamber of the regenerative tank furnace with a transverse direction of the flame and three pairs of gas burners is conducted. A zonal model of the furnace working chamber is developed to determine the optimum variant of the heat load distribution among the ports. A theoretical evaluation of the heat load in the case of increased (by 50%) furnace efficiency is carried out with allowance for the stability of the brickwork elements. © 1999 Kluwer Academic/Plenum Publishers.